#include <stdio.h>

int main()
{
    int a, b, c;
    while (scanf_s("%d %d %d/n", &a, &b, &c)==3)
    {
        if (a + b > c && a + c > b && c + b > a)
        {
            if (a == b && b == c && a == c)
            {
                printf("Equilateral triangle!\n");
                continue;
            }
            else if (a == b || b == c || a == c)
            {
                printf("Isosceles triangle!\n");
                continue;
            }

            else
            {
                printf("Ordinary triangle!\n");
                continue;
            }
        }
        else
        {
            printf("Not a triangle!\n");
            continue;
        }
    }

    return 0;
}